Pollination and Fertilization 



163 



tipped with yellow. The sugar bird sets free the arched style 

 oi Frotea, which scatters the pollen before the stigma is ripe. 



AVhen other flowers are closed for the season, the blue sage 

 {Salvia) may be depended upon to offer refreshments to visit- 

 ing bees. Down by the four-parted ovary there is a little 

 yellow gland where honey is made. At the entrance of the 

 flower a "rocking chair " is invitingly placed, made of the two 

 swinging stamens. One pollen chamber of each stamen has 

 been sacrificed to make the " seat " of the chair. As soon as 

 the bee touches this, the upper locules bend down and dust the 

 bee's back with pollen just along its hairy belt. The bee then 

 passes on to other sage blossoms. In some of these, stigmas 



I. II. 



Fig. 161. — Salvia. I. Corolla, the hood removed. II. Ditto with bee. 

 (From Henslow's " South .African Flowering Plants ".) 



which are ready to be pollinated arch down far enough to be 

 dusted with the precious load. 



Holes cut in the tube-; of flowers are evidence that a rob- 

 bery has been committed. The flower has been broken into 

 and pilfered of its honey without the insect performing any as- 

 sistance in conveying pollen. You can watch bumble-bees 

 bite holes in flowers which have tubes too long and narrow for 

 the bee to enter. Darwin tells us that honey-bees, which 

 usually pay down for each meal, are not above using the holes 

 made by bumble-bees the previous day. 



Orchids have gone to such an expense in making their 

 perianth attractive to insects, and in filling their long cornu- 



II * 



